But faced with another national tragedy, he did not long turn his focus away from the midterm elections or himself.
Nine days from elections that will determine the control of Congress, Trump stuck to his plans to appear at an agricultural convention and a political rally on Saturday.
Throughout the day, he expressed sorrow, called for justice and bemoaned hate, getting regular updates on the shooting. But he also campaigned for candidates, took shots at favourite Democratic targets House Minority Leader Nancy Pelosi and Senator Elizabeth Warren and made jokes about his hair.
At a massive rally in southern Illinois for Republican Mike Bost, Trump condemned the shooting as an “evil anti-Semitic attack”. But he said cancelling his appearance would make “sick, demented people important”. He pledged to change his tone for the evening and did cool some of his most fiery rhetoric.
The slaughter at Sabbath services followed a tense week dominated by a mail bomb plot with apparent political motivations and served as another toxic reminder of a divided nation.
It also again underscored Trump’s reluctance to step into the role of national unifier at tense moments as well as his singular focus heading into elections that could dramatically change his presidency.
Trump acknowledged the weight these moments carry, telling reporters that experiencing such events as president, “it’s a level of terribleness and horror that you can’t even believe. It’s hard to believe”.
The White House said Trump was getting regular briefings on the attack. He spoke with the governor of Pennsylvania and the mayor of Pittsburgh. He also spoke with his daughter Ivanka Trump and her husband, Jared Kushner, who are Jewish.
Shortly after returning to Washington late on Saturday, Trump ordered flags at federal buildings throughout the country to be flown at half-staff until October 31 in “solemn respect” for the victims.
Trump sought to energise turnout for Bost, who is fighting to hold on to a seat that was once a Democratic stronghold, but turned out for Trump in 2016.
To bolster his argument for sticking with the rally, Trump argued that the New York Stock Exchange was opened the day after 9/11, though in fact it was re-opened on September 17.
Speaking to a massive, cheering crowd at an airport hangar in southern Illinois, Trump said “the hearts of all Americans are filled with grief, following the monstrous killing”.
He told reporters before the rally that he would travel to Pittsburgh, though he did not offer details. He also sought to distance himself from the man arrested in the shooting, calling him “sick” and saying “he was no supporter of mine”.
Although his tone was softer, he still targeted Pelosi and Democrats and the crowd gleefully shouted “lock her up,” in reference to Hillary Clinton, one of the targets of the bomb plot. And he continued to emphasise his hardline immigration rhetoric.
“Republicans want strong borders, no crime, and no caravans,” Trump said.
Trump’s speech to a convention of the Future Farmers of America had all the hallmarks of a Trump rally, as the president riffed on trade, jobs and some of his political enemies.
At one point he also joked about his hair. He said it was ruffled by the rain as he left Washington, adding “I said, ‘maybe I should cancel this arrangement because I have a bad hair day”.
Trump offered an unsparing denunciation of anti-Semitism, which he said was the motive behind the attack, in contrast to remarks after clashes between white supremacists and counterprotesters in Charlottesville last year.
Then, he only inflamed tensions by blaming both sides for the violence.